As children return to school this fall, parents likewise return to worrying about ailments, both physical and emotional, that might befall their children on their way to —and in — the classroom. Whether it's bullying or head lice, thinking about what could go wrong can be overwhelming.

But not all school-related issues are created equal. In order to maintain their own sanity and the sanity of their kids, parents should try to think objectively about what issues truly warrant their attention. We spoke to a handful of experts to get their advice:

Parents and teachers are becoming more educated, but bullying still happens. In fact, one in four kids will experience bullying in some manner — whether they are victims, perpetrators or witnesses. It puts kids at risk for serious depression and even suicide, and as such, parents should be aware of what their children are doing at school and online.

Susan M. Swearer, a professor of school psychology at the University of Nebraska, Lincoln, and co-director of the Bullying Research Network, encourages parents to know who their children are talking to on the Internet and to have open conversations with kids about bullying at school. She also suggests that parents keep an eye out for warning signs — headaches, stomachaches, depression, anxiety — that their child is being victimized.

"When situations get difficult, that's when kids don't want to go to school," she says. "They may get depressed or feel worried and anxious." At that point, the parent should intercede with teachers and administrators.

According to Christopher Nowinski, the co-founder and executive director of the Sports Legacy Institute in Waltham, Mass., nearly 50% of students who play contact sports such as football and hockey will incur a concussion each season, as will 20% of athletes participating in other sports.

And while they need not put a child out of the running for the entire season, symptoms of concussions — headache, dizziness, confusion, nausea or vomiting, slurred speech, temporary loss of consciousness — can worsen if left untreated. In rare cases, concussions cause permanent injury or death.

"The key is to make sure that the concussion is identified, and that the athlete is seen by a doctor," Nowinski says. "Every parent should make sure that they educate their athlete on what a concussion is, and make sure they report what those symptoms are" so they can be treated immediately.

School refusal

Most kids will go through phases in which they don't want to go to school, but if those feelings start to manifest in more serious ways — if the child begins to shake, for instance, or cry uncontrollably on the way to school — parents should seek psychological help before the issue escalates into what's known as school refusal.

"Kids can be out of school for months on end" if the problem is allowed to get worse, says psychologist Stephanie Mihalas, an expert on pediatric behavior and emotional problems in children. "It can turn into full-blown panic disorder."

By seeking help at the first signs of severe anxiety, parents can frequently nip school refusal in the bud.

Emergency preparedness

It's critical that schools have a plan for keeping children out of harm's way, says Caroyln Duff, the president of the National Assn. for School Nurses.

Emergencies can include natural disasters and a police-ordered lockdown.

Schools should have "a plan in place, that's usually created by a team," Duff says. (The state of California requires that all public schools [K-12] operated by a school district have such a plan. ) Parents can find out more by speaking to school administrators.

Don't worry:

Head lice

Few ailments make parents more squeamish than the idea of tiny bugs crawling around on the scalps of their children. And they're not uncommon; the Centers for Disease Control and Prevention estimates that 6 million to 12 million children ages 3 to 11 get head lice each year.

"It's a nuisance, it disrupts family and life, kids can't go to school, and it's [an] economic" difficulty, says Risa Barash, the owner of Fairy Tale Hair Care, a line specializing in lice products.

But head lice are easily treatable and don't cause permanent damage.

Barash suggests that children avoid sharing hats and combs, or having head-to-head contact with other kids. The American Academy of Pediatrics also advises parents to do regular head checks on their children, particularly if they have attended a sleepover or camp.

A bad grade

Every now and then, kids with normally good grades get a low mark from a strict teacher. Parents might be inclined to become frantic when that happens, says Mihalas, but the best response to a single bad grade is to remain calm and demonstrate how the child might work through the situation.

"One bad grade on a test is not a big deal," she says. "If the parent shows that they're hysterical," it sets a bad example for the child.

Incontinence

It's fairly common for young children to have accidents at school, but, Duff says, "it generally happens for reasons unrelated to health issues."

Most teachers and school staff are trained to handle an incident discreetly, and the best thing a parent can do is send his or her child to school with a change of clothes in their backpack.

First-day jitters

Many parents dread the first day of school, not because they have to say goodbye to their precious charges, but because the possibility exists that kids will become upset.

This, says Duff, is not necessarily a reason to become concerned.

Parents can minimize back-to-school jitters by bringing their child to the school before the first day to walk around and get a sense of the environment. Some schools also have meet-the-teacher nights, where parents and kids can get to know their new instructors.